A DC-DC converter is a form of voltage converter that receives input of a DC voltage and modifies it to output a DC voltage of a different voltage level. Different topologies of converters enable boost and buck operations. DC-DC converters are desirable to use in powering portable devices such as wireless devices, since they can reduce the current drawn from a battery power supply. Many types of DC-DC converters exist, including pulse width modulation (PWM) converters and pulse frequency modulation (PFM) converters. Different converters may be preferable for certain applications. For example, a PFM converter maximizes efficiency over a wider range of load currents than does a PWM DC-DC converter. However, one drawback of a PFM converter is that its switching operations can cause interference in radio frequency (RF) circuits that is difficult to control, since the interfering energy is spread over wide and unpredictable frequency bands.